At the beginning of your upkeep, create a random token that's a copy of one of the following:
Aven Mindcensor, Drannith Magistrate, Ghostly Prison, Hushbringer, Smokestack, or Thalia, Guardian of Thraben. (There are six of them, so one easy way to select is to roll a D6.)
When Form of the Stax Player leaves the battlefield, sacrifice each token created with it.
Format Legality
Standard Not_legal
Pioneer Not_legal
Modern Not_legal
Legacy Not_legal
Vintage Not_legal
Commander Not_legal
Pauper Not_legal
